Microsurgical fenestration and cystoperitoneal shunt through preauricular subtemporal keyhole craniotomy for the treatment of symptomatic middle fossa arachnoid cysts in children

INTRODUCTION

The optimal surgical treatment for symptomatic middle fossa arachnoid cyst is still controversial. The most leading therapeutic options include cyst shunting and fenestration (endoscopic, microsurgical). We present our experience on surgical treatments of arachnoid cysts.

PATIENTS AND METHODS

A retrospective data review of 16 children who underwent keyhole craniotomy for microsurgical fenestration and shunting of middle fossa arachnoid cysts between 1999 and 2012 was performed after institutional review board approval. The average patient age was 6.1 years. The average follow-up period was 36.5 months. There were ten male and six female patients in the series. Indications for surgery included intractable headaches (50%), increasing in cyst size (18.75%), and seizures (31.25%). All patient records were reviewed for their clinical presentation, classification, cyst resolution, symptom resolution, and cyst outcomes. After surgery, all patients underwent assessments of clinical and radiological improvement.

RESULTS

Postoperative complications were observed in two cases: progressively resolving monoparesia in one case and resolving epileptic seizure with monotherapy in the other. All patients had a satisfactory clinical outcome, and in 87.5%, there was either a decrease in the size or a complete disappearance of the MFAC. Nevertheless, three (18.75%) of all patients needed shunt revision because of shunt dysfunction. Complication related to surgical technique was cerebrospinal fluid leak which spontaneously resolved in one patient.

CONCLUSION

Microsurgical fenestration with keyhole craniotomy to provide passage between cysts to basal cisterns together with cystoperitoneal shunting during the same operation is still an effective and safe method in cases with symptomatic middle fossa arachnoid cysts in children.

Effects of ebselen on ischemia/reperfusion injury in rat brain

AIM

Interruption of blood flow may result in considerable tissue damage via ischemia/reperfusion (I/R) injury-induced oxidative stress in brain tissues. The aim of the present study was to investigate the effects of Ebselen treatment in short-term global brain I/R injury in rats.

MATERIAL AND METHODS

The study was carried out on 27 Wistar-albino rats, divided into three groups including Sham group (n = 11), I/R group (n = 8) and I/R+Ebselen group (n = 8).

RESULTS

Malondialdehyde (MDA) levels were significantly increased in I/R group in comparison with the Sham group and I/R+Ebselen group (p < 0.001 and p < 0.01). Superoxide dismutase (SOD) activity was significantly lower in I/R group in comparison to both Sham (p < 0.001) and I/R+Ebselen (p < 0.01) groups. Similarly, SOD activity was decreased in I/R+Ebselen group when compared with Sham group (p < 0.001). Sham and I/R groups were similar in terms of nitric oxide (NO) levels. In contrast, the NO level was lower in I/R+Ebselen group when compared with Sham (p < 0.001) and I/R (p < 0.01) groups. There was no significant difference among the groups in terms of glutathione peroxidase and catalase activities. In histopathological examination, the brain tissues of rats that received Ebselen showed morphological improvement.

CONCLUSION

Ebselen has neuron-protective effects due to its antioxidant properties as shown by the decrease in MDA overproduction, increase in SOD activity and the histological improvement after administration of Ebselen to I/R in brain tissue.

Non-traumatic spontaneous acute epidural hematoma in a patient with sickle cell disease

A 19-year-old female with sickle cell anemia (SCD) was referred to our hospital after two days of hospitalization at another hospital for a headache crisis. This headache crisis was due to a raised intracranial pressure; these symptoms were noted and included in her comprehensive list of symptoms. There was an acute drop in the hemoglobin and hematocrit levels. The cranial CT scan demonstrated a left fronto-parietal acute epidural hematoma (AEH) and a calvarial bone expansion, which was suggestive of medullary hematopoiesis. The patient underwent emergent craniotomy and evacuation of the hematoma. There were no abnormal findings intra-operatively apart from the AEH, except skull thickening and active petechial bleeding from the dural arteries. Repeated CT scan showed a complete evacuation of the hematoma. The possible underlying pathophysiological mechanisms were discussed. In addition to the factors mentioned in the relevant literature, any active petechial bleeding from the dural arteries on the separated surface of the dura from the skull could have contributed to the expanding of the AEH in our patient. Neurosurgeons and other health care providers should be aware of spontaneous AEH in patients with SCD.

Protrusion of a peritoneal catheter via abdominal wall and operated myelomeningocele area: a rare complication of ventriculoperitoneal shunt

BACKGROUND

Ventriculoperitoneal shunting is mostly used in the treatment of hydrocephalus, and many complications have been reported with this method. These complications include obstruction, mechanical shunt failure, infection, and abdominal complications. Abdominal complications include intestinal obstruction, volvulus, peritonitis, peritoneal cyst, cerebrospinal fluid ascites, as well as migration of the distal catheter via the intestinal tract, umbilicus, scrotum, and vagina. Various mechanisms have been suggested with regards to the catheter migration.

CASE REPORT

We present a case of a 21-month-old female patient who had myelomeningocele at birth. She underwent repair of the myelomeningocele at the age of 10 days. After 4 months, cranial computed tomography revealed hydrocephalus, and ventriculoperitoneal shunt was placed. Because of shunt dysfunction, a new ventriculoperitoneal shunt system was installed at the age of 12 months. Eight months later, her mother noticed the protrusion of peritoneal catheter via abdominal wall and repaired myelomeningocele area. Revision of the lower end of the shunt was done, and myelomeningocele area was repaired again.

CONCLUSION

We report a unique patient with the protrusion of the distal catheter through repaired myelomeningocele area and abdominal wall in the lumbar region.

Protective effects of minocycline against short-term ischemia-reperfusion injury in rat brain

The aim of this study was to assess the effects of minocycline on cerebral ischemia-reperfusion (I/R) injury in rats. The study was carried out on 24 male Wistar albino rats, weighing 200-250 g, which were divided into three groups: (i) control (n = 8), (ii) I/R (n = 8) and (iii) I/R + minocycline (n = 8). Minocycline was administrated at a dose of 90 mg/kg p.o. to the I/R group 48, 24 and 1 h before ischemia. Following bilateral exposure of the common carotid arteries by anterior cervical dissection and separation of the vagus nerve, I/R injury was performed by occlusion. Following reperfusion, malondialdehyde (MDA), superoxide dismutase, glutathione peroxidase and catalase levels in the blood and brain tissue, and creatine kinase (CK), CK-BB, lactate dehydrogenase (LDH), neuron-specific enolase (NSE) and protein S100β levels in the blood were measured and the histopathological changes were monitored. Regarding histopathological evaluation, symptoms of degeneration were significantly improved in the I/R + minocycline group compared to the I/R-only group. Statistical analysis of the biochemical parameters revealed significant differences in MDA (p < 0.001), nitric oxide (p < 0.05), CK (p < 0.05) and CK-MB (p < 0.05) levels between the I/R + minocycline group and the I/R group. According to the literature, the effect of minocycline is firstly assessed by LDH, CK-MB, NSE and S-100β analysis in addition to antioxidant status and histopathological analysis.

Microsurgical management of non-neurofibromatosis spinal schwannoma

INTRODUCTION

The aim of this study is to assess the clinical properties and surgical results of patients diagnosed with spinal schwannomas without neurofibromatosis (NF) properties.

PATIENTS AND METHODS

The data obtained from 35 patients who underwent resection of spinal schwannomas were analyzed. All cases with neurofibromas and those with a known diagnosis of NF Type 1 or 2 were excluded. 35 patients underwent surgery for spinal schwannoma at our institution between January 1997 and 2010. The data were gathered retrospectively from medical records and included clinical presentation, tumor location and post-operative complications. All cases were surgically excised, and they were confirmed to be schwannomas by pathologists with histopathological sections in paraffin stained with hematoxylin-eosin.

RESULT

We treated 35 (20 males and 15 females) patients with spinal schwannomas. The mean age of the patients was 47.2 (between 13 and 76) years. Of the cases, six schwannomas were located in the cervical spine, four in the thoracic spine, two in cervico-thoracic area, 10 in the thoraco-lumbar area and 13 in the lumbar spine. Two patients had malignant schwannomas that were recurrent. Of the 35 cases, the schwannomas were intradural-extramedullary in 30 cases (86%), intradural-intramedullar in 2 cases (6%), and extradural in 3 cases (9%).

CONCLUSION

Spinal schwannomas may occur at any level of the spinal axis and are most frequently intradural-extramedullary. The most common clinical presentation is pain. Most of the spinal schwannomas in non-NF patients can be resected completely without or with minor post-operative deficits. This knowledge may help us to create a strategy for total resection of a spinal schwannomas.

Protective effects of edaravone on experimental spinal cord injury in rats

BACKGROUND

Spinal cord injury (SCI) is a leading cause of morbidity and mortality among youth and adults. Secondary injury mechanisms within the spinal cord (SC) are well known to cause deterioration after an acute impact. Free radical scavengers are among the most studied agents in animal models of SCI. Edaravone is a scavenger of hydroxyl radicals.

METHODS

We aimed to measure and compare the effects of both methylprednisolone and edaravone on tissue and on serum concentrations of nitric oxide (NO), malondialdehyde (MDA) levels, superoxide dismutase (SOD) activity, glutathione peroxidase (GSH-Px) activity, and tissue total antioxidant capacity (TAC) in rats with SCI. SCI was induced in four groups of Wistar albino rats by a weight-drop method. The neurological function of the rats was periodically tested. At the end of the experiment, blood samples were collected, and SC tissue samples were harvested for biochemical evaluation.

RESULTS

The tissue level of NO was decreased in the edaravone-treated group compared with the no-treatment group (p < 0.05). The tissue levels of SOD and GSH-Px were higher in the edaravone-treated group than in the no-treatment group (p < 0.05). The serum levels of NO were lower in the edaravone-treated and methylprednisolone-treated groups than in the no-treatment group (p < 0.05). The serum levels of SOD in the edaravone-treated group did not differ from those of any other group. The serum levels of MDA in the edaravone-treated and no-treatment groups were higher than in the two other groups (p < 0.05). Tissue levels of MDA in the edaravone-treated group were lower than in the no-treatment group (p < 0.05). Tissue levels of TAC in the edaravone-treated group were higher than in the no-treatment and methylprednisolone-treated groups (p < 0.05). The neurological outcome scores of the animals in treatment groups did not depict any statistically significant improvement in motor functions. However, edaravone seemed to prevent further worsening of the immediate post-SCI neurological status.

CONCLUSION

Our biochemical analyses indicate that edaravone is capable of blunting the increased oxidative stress that follows SCI. We show, for the first time, that edaravone enhances the TAC in SC tissue. This beneficial effect of edaravone on antioxidant status may act to minimize the secondary neurological damage that occurs during the acute phase after SCI.

The effect of polymorphisms in the promoter region of the MMP-1 gene on the occurrence and invasiveness of hypophyseal adenoma

BACKGROUND

The matrix metalloproteinase-1 enzyme (MMP-1, also called collagenase 1) plays a key role in turnover of collagen fibers in the intercellular matrix. Insertion of a guanine residue was found within the promoter region of the MMP-1 gene. We found that MMP-1 levels increased approximately twofold over normal when this insertion was present, enabling MMP-1 to facilitate tumor invasion and metastasis. MMP-1 is also believed to play a role in tumor development. The aim of our study is to investigate the effect of polymorphisms in the promoter region of the MMP-1 gene on the development of benign and invasive hypophyseal adenomas.

PATIENTS AND METHODS

Thirty patients with hypophyseal adenomas diagnosed by radiological examination underwent surgical removal, and the diagnosis was confirmed using immunohistochemical staining of the pathology specimens. We found that ten of these patients had invasive adenomas confirmed by radiological examination and immunohistochemical staining. DNA isolation was performed on all specimens, and 5-cc venous blood samples were obtained from all patients as well as 30 volunteers using the Qiagen QIAquick kit. Promoter regions of MMP-1 genes from the DNA samples were amplified using polymerase chain reaction (PCR) and primers designed for the site-directed mutation method. Following PCR, a guanine residue within the promoter region of the MMP-1 gene was identified using the restriction fragment length polymorphism method and the ALU I restriction enzyme. Three genotypes were detected in a genotyping assay: 2G/2G, 1G/2G, and 1G/1G.

RESULTS

Of the surgically treated patients, 36.6% had the 2G/2G genotype, 46.6% had the 1G/2G genotype, and 16.6% had the 1G/1G genotype. The 2G allele frequency was found to be 83.4%. In 90% of cases of invasive adenoma, a homozygous 2G/2G genotype was detected.

DISCUSSION

The risk for development of hypophyseal adenoma may be greater in patients with the 2G allele. In cases of existing hypophyseal adenoma, those with the homozygous 2G allele tend to be invasive.

Differentiation of healthy brain tissue and tumors using surface-enhanced Raman scattering

Surface-enhanced Raman scattering (SERS) is a powerful technique for characterization of biological samples. SERS spectra from healthy brain tissue and tumors are obtained by sudden freezing of tissue in liquid nitrogen and crashing and mixing it with a concentrated silver colloidal suspension. The acquired spectra from tissues show significant spectral differences that can be used to identify whether it is from a healthy region or tumor. The most significant change on SERS spectra from the healthy/peripheral brain tissue to tumor is the increase of the ratio of the peaks at around 723 to 655 cm(-1). In addition, the spectral changes indicate that the protein content in tumors increases compared to the peripheral/healthy tissue as observed with tumor invasion. The preliminary results show that SERS spectra can be used for a quick diagnosis due to the simplicity of the sample preparation and the speed of the spectral acquisition.